Bone fixation systems typically maintain bone fragments in position following osteotomy or reduction procedures in order to initiate bone healing. Bone fixation systems include implants, bone fixation members, and instruments. The instruments typically position the implants relative to bone. In some cases, instruments may manipulate the implants into the appropriate position in order to achieve desired restoration of anatomy following a cut or fracture. For instance, a bone fixation member, such as a cable tie, can be wrapped about bone segments. A tensile force applied the cable tie tightens the cable tie around the bone segments attaining the desired reduction. In another example, after a craniotomy, an inner plate positioned inside the cranium next to a bone flap and an outer plate positioned outside cranium hold the bone flap in position. A guide wire attached the inner plate is tensioned, causing the outer and inner plates to clamp the bone flap to the cranium.